A flexible printed circuit, or FPC as it is commonly referred to in the industry, is basically a strip or cable comprising a plurality of embedded electrically conductive lines. The flexible printed circuit is typically used for providing an electrical connection between electrical components on a first printed circuit board and electrical components on a second printed circuit board. Presently, there are two types of basic devices being used for providing an electrical interface between the flexible printed circuit and each of the printed circuit boards. These two types of connectors are typically referred to as a zero insertion force (ZIF) connector and a board-to-board connector.
First, mating the zero insertion force (ZIF) connector located on the printed circuit board with the flexible printed circuit having a plated, typically flat pad attached to a first end of the flexible printed circuit is well known in the art.
However, one of the drawbacks of using the zero insertion force connector is that, because of the standardized specification for the width of the connector pads, the density of lines obtainable within a predetermined amount of space is limited. With the continual miniaturization of certain electrical devices, such as portable computers, it is sometimes desirable to obtain a higher density of conductor lines than is available from using a zero insertion force connector between the flexible printed circuit and the printed circuit board. Furthermore, since some printed circuit boards are manufactured with different types of connectors, a zero insertion force connector may not be an available option.
Second, board-to-board connectors such as (1) a board mounted connector located on the printed circuit board, and (2) a mating connector attached to the first end of the flexible printed circuit, wherein the mating connector interfaces with the corresponding board mounted connector, is also well known in the art.
Although these mating connectors are designed to be reliably connected and disconnected through hundreds, and even thousands, of mating cycles, they are typically only connected and disconnected just a few times during manufacturing and maybe a few more times during a repair job. Therefore, one of the drawbacks of using the board mounted connector with the corresponding mating connector is the increased cost associated with paying for a level of durability that is not required for certain electrical interfaces.
Often times, the mating connectors are single sourced as matching proprietary parts by the same manufacturer that manufactures the corresponding board mounted connector. Therefore, with the absence of competition, the mating connectors sold and made available by the single source manufacturer are relatively more expensive than similar non-proprietary parts sold and made available by various competing manufacturers.
Furthermore, being tied to a single source manufacturer for the mating connectors increases the risk that the availability of these mating connector parts may be interrupted as a result of problems affecting the single source manufacturer. With a single source manufacturer producing these mating connector parts, there are no other manufacturers to serve as backup suppliers. This potential lack of availability could result in the delayed shipment of products that make use of the mating connectors.
In addition, since these mating connectors are typically soldered onto the flexible printed circuit, expensive heat resistant base materials are required for the design of the flexible printed circuit.
Therefore, a better solution is needed to provide an electrical interface between the flexible printed circuit and the printed circuit board, wherein the interface between the flexible printed circuit and the printed circuit board (1) accommodates a higher density of electrically conductive lines than the zero insertion force connector, (2) is readily available to meet demand with a lower risk of interruption in supplies, and (3) provides a cost savings over the board mounted connector-mating connector combination.
It is understood that the term "board mounted connector" is used herein as a clarifying term to describe a connector that happens to be mounted to the printed circuit board, as in a preferred embodiment described in greater detail below. The term "board mounted connector" however shall not be limited to connectors mounted to a board. For example, the board mounted connector may actually be connected to the printed circuit board via a second flexible printed circuit such that the board mounted connector and corresponding mating connector act as an interface between two flexible printed circuits which in turn connect two printed circuit boards, or electrical elements.